Ciliary Body anatomy and physiology Flashcards
outer to the ciliary body is
Sclera
Inner to the ciliary body are
The posterior and vitreous chambers
Anterior to the ciliary body
Continuous with the iris, TM, and SS
Posteriorly, continuous with
The choroid and retina.
Transition between the ciliary body and retina/choroid
Ora serrata
Location of pars plicate and pars plana
Pars plicata- wider anterior region.
Pars plana- Thinner, flatter posterior region.
Where are ciliary processes located?
Para plicata- wider anterior region.
70-80 processes.
What are ciliary processes composed of?
Where do they extend into?
What do they produce?
Composed of projections of ciliary stroma covered by pigmented and non pigmented epithelium.
Extends into the posterior chamber.
Produces aqueous humor.
Flow of aqueous humor
From the ciliary processes located in pars plicata.
Into the posterior chamber, between the lens and the iris, though the pupil, into the anterior chamber.
Where does pars plana extend from and to
From the posterior pars plicata to ora serrata.
What part of the ciliary body appears serrated
Pars plana in the area of ora serrata.
Layers of the ciliary body from outer to inner
Outer Superciliaris Muscles Stroma Pigmented Non pigmented Inner
Supraciliaris. What is it? What is it continuous with?
Potential space between ciliary body and sclera. Continuous with the surachoroid space (between choroid and sclera)
Ciliary muscle. Composed of what?
Surrounded by what?
Smooth muscle fibers with longitudinal, radial, and circular orientations.
Surrounded by the ciliary stroma.
Longitudinal muscle fibers attach to
The SS and TM
Ciliary stroma is composed of what?
Vascularized, loose CT (collagen, fibroblasts, ground substance) with melanocytes and WBCs.
Pigmented epithelium
- How many layers?
- What junctions?
Single layer of epithelial cells that are apex to apex with the non pigmented epithelium.
Gap junctions.
Non pigmented epithelium
Most inner layer that lines the posterior chamber and part of the vitreous chamber.
Single layer of epithelial cells joined by tight junctions that form a complete barrier.
Zonules arise from the BM of non pigmented epithelium, which faces the posterior chamber.
Where do zonules arise from?
Arise from the basement membrane of these cells. Insert into the lens capsule in the equatorial regions of the lens.
Blood supply to the ciliary body
The major arterial circle of the iris (MACI).
Supplies the ciliary body.
Capillaries are in the ciliary stroma. Are they fenestrated or non?
They are highly fenestrated. Allow water, molecules, and ions to leak out of the capillaries and enter the stroma.
Innervation to the ciliary body
Parasympathetic.
How is aqueous humor made?
It is a filtrate of blood.
What does aqueous humor consist of?
Water, molecules, and ions that leak out from the capillaries in the ciliary stroma.
What force makes the IOP?
Aqueous humor exerts a force on the internal surface area of the anterior eye.
2 routes of aqueous humor drainage
- Trabecular (70-90%)
2. Uveoscleral (10-30%)
Trabecular route of aqueous drainage
Anterior chamber Posterior trabecular meshwork Schlemms canal Aqueous veins to episcleral veins OR intrascleral collector channels to intrascleral venous plexus to conj/episcleral veins.
Uveoscleral route of aqueous drainage
Anterior chamber Iris root Ciliary body Supraciliaris Suprachoroidal space Vortex veins or absorbed into scleral stroma.
